Window frame

The heat transfer characteristics in building window frame have significant three-dimensional characteristics, but window U-value model are often used in most building codes for thermal analyses to simplify the calculations. State model reduction techniques were used to develop loworder three-dimensional heat transfer model for window frame, which is efficient and accuracy. The method was validated for a envelope designs by comparing the with complete 3-D models.

An efficient thermal insulation of glazing or window frame is important because poor insulating performance usually cause the largest heat loss on any buildings. As one of the methods decreasing heat loss of buildings, we proposed a dynamic insulation system applied to window frame, and its energy saving performance and applicability for buliding had been confirmed using numerical simulation in previous study [1].